Re: Is 00:00:00:00:00:00 special?

Lloyd Parkes <[email protected]> Thu, 20 Nov 2025 17:15:07 +1300
Newsgroups gmane.os.netbsd.devel.network
Message-ID <[email protected]>
I can't see why an all 0 MAC would be invalid. The OUI 00-00-00 is valid 
and owned by Xerox.

Maybe something in the EUI64 generation code looks at the all zero MAC 
and takes that as an in in-band error value?

Ngā mihi,
Lloyd

On 20/11/2025 16:59, Mouse wrote:
> Is the all-zero MAC address special?  Thanks to an unusual hardware
> situation, I just booted a SPARC such that le0 thinks its MAC is
> all-0-bits.  (Booted from disk, not netboot, to be sure.)
>
> But IPv6 failed to attach at boot time, saying it failed to get EUI64,
> which is why I'm asking.  I can't recall hearing of any way in which
> the all-0 MAC would be invalid, but _something_ seems to think it is;
> it looks to me like a perfectly good globally-administered unicast
> address.  It seems to work fine for IPv4, though of course (like any
> MAC) there can be at most one such in any broadcast domain unless
> you're doing something fancy.
>
> Anybody happen to know?
>
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